Device for crimping synthetic thread bundles or strips

ABSTRACT

A device for crimping synthetic thread bundles or strips has a machine frame, two rollers supported in a machine frame and forming between their jacket a narrow roller gap for delivering a thread bundle or strip, with the first roller provided on its face ends with edge disks which embrace the second roller with slight play and form there, between an annular channel, the edge disks having inside faces forming two opposed boundary faces, a compression chamber having a rectangular cross-section, enclosed by boundary faces, and located in the annular channel between the edge disks, an outer adapter contacting the second roller in scrapper like fashion, engaging the annular channel and having a wall face oriented toward the first roller and forming a third boundary face of the compression chamber, and drive mechanisms provided for the two rollers and having motors which are designed for a circumferential speed of the rollers of up to at least 1,000 m/min.

BACKGROUND OF THE INVENTION

The invention relates to a device for crimping synthetic thread bundlesor strips.

A device that already has the characteristics of this preamble is knownfrom British Patent 487 711. In this device, the two rollers that can bedriven in contrary directions are disposed--as is usual in compressioncrimping devices--above one another. The upper roller is provided withedge disks. The compression chamber has a fixed bottom plate, which isdisposed parallel to and a short distance from the plane of the rollergap, and a pivotable top plate. The opening of the orifice of thecompression chamber is located at the level of the plane of the rollergap. The compression chamber extends approximately as far as the edge ofthe edge disks, whose diameter is approximately 1.5 times the rollerdiameter and cannot be selected substantially larger, for geometricreasons. The compression chamber is therefore comparatively small,compared with the diameter of the rollers.

German Patent Disclosure DE-OS 21 15 688 describes a device in whichagain one of the two rollers is provided with edge disks. In thisdevice, the compression chamber is substantially larger, compared to thedimensions of the rollers. However, the inner faces of the edge disksform the lateral boundary faces only in a small region in thesurroundings of the roller gap. By far the greater portion of the sidefaces is covered by fixed walls. There is necessarily a seam between theedge disks, which rotate with the rollers, and the fixed walls

The same is true for another device, which is described in German PatentDisclosure DE-OS 20 21 103.

From German Patent Disclosure DE-OS 35 03 447, a device is known whichis distinguished from the last two devices explained above in particularthat the two rollers each have one edge disk, and the two edge disks aremounted on opposed face ends.

The subject of German Patent Disclosure DE-OS 38 36 646 is a compressioncrimping device, in which one roller is disposed in the interior ofanother roller, the latter embodied as an annular roller. There is aroller gap between the jacket face of the inner roller and the insideface of the annular roller.

One of the two rollers, which can be driven in the same direction, isprovided with edge disks, which embrace the other roller. The edgedisks, over the entire length of the compression chamber, form twoopposed lateral boundary faces. Other boundary faces are formed by theinside face of the annular roller and by the jacket face of the innerroller. The compression chamber is therefore like the pointed end of acrescent, in side view. Because of the curved form, there isnecessarily--in a deviation from all the other devices explainedabove--a spacing between the orifice opening and the plane of the rollergap. By the provision of a roller in the interior of an annular roller,the geometric conditions are made quite complicated and are greatlyrestricted. The compression chamber itself is therefore--compared withthe dimensions of the overall device--rather small. Problems arise,particularly with respect to delivering the thread bundle to becompressed to the roller gap and drawing off the crimped material.

In many modern crimping devices, as can be learned from European PatentDisclosure EP 0 256 257 A2, for instance, a rotating pressure disk islet into a fixed side plate of the compression chamber and seals off theespecially critical surroundings of the roller gap. Between the pressuredisk and the side plate, there is intrinsically a seam. Compressionchambers of this or similar design generally process yarn cables of veryhigh titer of up to a few million dtex, at low speeds of up to about 300or at the most 400 m/min.

The invention takes as its departure the problems presented particularlyin crimping machines that run at substantially higher speeds. One suchcrimping machine is described for instance in German Patent DisclosureDE-OS 33 32 387. The compression chamber of rectangular cross section isenclosed by smooth boundary walls which are immovable in operation.Although speeds of 2000 m/min are mentioned in this reference,nevertheless in actual use this machine usually runs at speeds of up toabout 1000 m/min and handles titers in the range of approximately 10,000to 100,000 dtex. In operation, friction between the wall faces and thethread plug found in the compression chamber creates heat, so that athigh speed the threads can even melt. There are accordingly limits toincreasing the operating speed. At high speeds, increasing problems alsoarise from the fact that the thread catches at the gaps between therotating roller and the stationary wall faces.

The inventors have recognized that the combination of characteristicsrecited in the preamble and known from British Patent 487711 offers thepossibility, in high-speed crimping, of reducing the heating caused byfriction considerably and reducing the danger that the threads willcatch. Each face element of the inside faces of the edge disks is incontact with the thread plug for only a relatively brief period of timeper revolution and thus is heated hardly at all. During the brief phaseof contact, the relative speed between the plug and the inside faces ofthe edge disks is markedly lower than in compression chambers with fixedwall faces. The side wall faces are free of seams, so the thread isprevented from catching, at least in those regions.

SUMMARY OF THE INVENTION

Accordingly, in accordance with the present invention a device forcrimping synthetic thread bundles or strips is proposed which is afurther improvement of the existing devices.

In keeping with these objects and with others which will become apparenthereinafter, one feature of present invention resides, briefly stated ina device for crimping synthetic thread bundles or strips, which has amachine frame, two rollers supported in a machine frame and formingbetween their jacket a narrow roller gap for delivering a thread bundleor strip, the rollers including a first roller and a second rollerarranged so that the first roller is provided on its face ends with edgedisks which embrace the second roller with slight play and form therebetween an annular channel, the edge disks having inside faces whichover an entire length of the compression chamber from the roller gap tothe orifice and form two opposed boundary faces, a compression chamberto which the thread bundle or strip is delivered and which has anorifice, the compression chamber having a rectangular cross-section andbeing enclosed by first, second, third, and fourth boundary faces, thecompression chamber being located in the annular channel between theedge disks, an outer adapter contacting the second roller in scrapperlike fashion, the outer adaptor engaging the annular channel and havinga wall face oriented toward the first roller and forming said thirdboundary face of the compression chamber, and drive mechanisms providedfor the two rollers and having motors which are designed for acircumferential speed of the rollers of up to at least 1,000 m/min.

In accordance with another feature of the present invention, the orificeis spaced apart from the plane of the roller gap, specifically on theside on which the first roller is located, and also the third boundaryface and the fourth boundary face opposite it are curved cylindricallyover at least part of their length, while the axes of curvature arelocated on the same side of the plane of the roller gap as the firstroller.

When the device is designed in accordance with these features, it makesit possible to increase the dimensions of the compression chambermarkedly, compared with the diameter of the rollers.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an exemplary embodiment in a perspective view.

FIG. 2 shows core parts of the exemplary embodiment of FIG. 1, again ina perspective view.

FIG. 3 shows the parts shown in FIG. 2, in a side view and partly insection;

FIG. 4 shows another exemplary embodiment in a side view analogous toFIG. 3.

FIG. 5 shows a third exemplary embodiment, again in a side viewanalogous to FIG. 3.

DESCRIPTION OF PREFERRED EMBODIMENTS

The device of the invention in general includes two rollers 1, 2, whoseaxes are parallel to one another and spaced apart such that a narrowroller gap 3 is located between the jacket faces of the two rollers 1,2. The first roller 1 differs from the second roller 2 in that it isprovided with edge disks 4, 5 on both of its end faces. These disksembrace the second roller 2, so that a slight play exists between theinside face of one edge disk 4, 5 and the end face, oriented toward it,of the second roller 2. The inside clearance between the two edge disks4, 5 is 15 mm, for instance. As a rule, it is between 10 and 25 mm.

In all the drawing figures, the two rollers 1, 2 are disposed verticallyone above the other, specifically in such a way that the first roller 1,having the edge disks 4, 5, is at the bottom. Although this arrangement,which is preferred in many cases, is not absolutely necessary and inpractice may optionally be modified to suit conditions in an individualcase, nevertheless for the sake of simplicity and clarity in thisdescription the first roller 1, that is, the roller with the edge disks4, 5, will always be called the "lower roller 1", and the other roller 2will be called the "upper roller 2". Accordingly, the word "lower" ineach case refers to the portion of the device of the invention in whichthe first roller 1 is located, while the term "upper" refers to theportion in which the second roller 2, which has no edge disks, islocated.

FIG. 1 shows two rectangular frames 6, 7. The lower frame 6 is connectedimmovably to a load-bearing construction, not shown. It has a side wall8 and an opposed side wall, not visible in the drawing, as well as anend wall 9 and an opposite end wall not visible in the drawing.

The upper frame 7 is constructed correspondingly and has side walls 10,11 and end walls 12, 13. The arrangement of the two frames 6, 7 isreminiscent of two boxes stacked on one another.

One upward-pointing tab 14, 15 each is solidly connected to the sidewall 8 of the fixed frame 6 and to the opposed side wall, which isconcealed in the drawing. The tabs 14, 15 are provided with bores, inwhich a pivot shaft 16 is located. The ends of the pivot shaft 16 passthrough the side walls 10, 11 of the upper frame 7 in the vicinity ofthe end wall 13, so that this frame is pivotable about the pivot shaft16. To make the pivoting possible, the side walls 10, 7 have a curvedrounded feature 17.

A shaft 18 is supported i the fixed frame 6, and its two ends protrudeoutward from the side walls. On the one end that passes through the sidewall 8, the lower roller 1 is seated. The other end of the shaft 18 iscoupled, via a gear not visible in the drawing, to a motor 19 disposedbelow the fixed frame 6.

A shaft 20 is supported in a corresponding way in the pivotable frame 7between the pivot shaft 16 and the end wall 12. On the end that passesthrough the side wall 10, the upper roller 2 is seated. The upper end ofthe shaft 20 is coupled, via a toothed belt gear 21, with a motor 22mounted on the end wall 13 adjacent to the pivot shaft 16.

The two motors 19, 22 are synchronized electronically, so that inoperation the rollers 1, 2 rotate at the same circumferential speed butin opposite directions, as indicated by arrows 23, 24. In all theexemplary embodiments, the two rollers 1, 2 have the same diameter.Their rotary speeds therefore match. The motors 19, 20 are designed suchthat circumferential speeds of up to at least 1000 m/min are attainable.The preferred range begins at 2000 m/min and extends to above 3000m/min.

A bidirectional cylinder 25 is secured to the end wall 9 of the fixedframe 6. The associated piston rod 26 engages an eyelet 27, which isconnected to the end wall 12 of the pivotable frame 7. In operation, thepiston and cylinder unit 25, 26 is switched in such a way that the upperroller 2 is loaded with a force acting in the direction of the lowerroller 1. With this force, the upper roller 2 is pressed against thelower roller 1, or against the thread material located in the roller gap3.

A disk 28 is seated between the upper roller 2 and the side wall 10,adjacent to it, of the pivotable frame 7; the disk is solidly connectedto the side wall 10 and, particularly in the region remote from thepivot shaft 16, it protrudes past the circumference of the upper roller2. An outer adapter 29 is secured to it. The adapter engages the annularchannel, which is bounded by the jacket face 30 of the lower roller 1and the inside faces of the edge disks 4, 5, which are secured forinstance by screws 31 to the face ends of the lower roller 1 and have adiameter that is greater by 25 to 35% than the jacket face 30 of thisroller.

The outer adapter 29, in the exemplary embodiment shown in FIGS. 1-3,comprises a base body 32 and a flap 33 pivotably connected to it. Thebase body 32 has a curved outer face 34, which conforms closely to thejacket face of the upper roller 2, and which with a lower wall face 35,oriented toward the lower roller 1, forms an acute-angled edge 36 in thevicinity of the roller gap 3 that is similar to the stripper edge of ascraper.

The base body 32 is provided with oblong slots 37, 38, which aredisposed on a circular arc whose center point is located on the axis ofthe upper roller 2. The long sides of the oblong slots 37, 38 arecorrespondingly curved. Tangs 39, 40 which are joined on one end to thedisk 28 and are threaded on the other, free end engage the oblong slots37, 38. It thus becomes possible for the base body to be displaced in alimited angular range on the circular arc and the axis of the upperroller 2, and by means of screw nuts, not shown, that are seated on thetangs 39, 40, to lock the base body in any desired position within thisangular range.

In the vicinity of the edge 36, on the side toward the upper roller 2,the base body 32 has recesses 41. The recesses can be connected, viabores 32 provided with female threads, to lines for delivering a mediumthat is under pressure. The delivery of compressed air in particularbrings about cooling during operation and prevents threads from catchingin the gap between the jacket face of the upper roller 2 and the edge36.

The flap 33 can be loaded, by means of a pneumatic or hydraulic contactpressure device, with a force acting in the direction of the axis of thelower roller 1. A pressure cylinder 43 is secured to a retaining block44, which is screwed to the disk 28. An associated piston rod 45,oriented approximately radially to the lower roller 1, engages the flap3.

The wall face 46 of the flap 33 toward the lower roller 1 is curvedcylindrically. The radius of curvature is at least equal to the radiusof the jacket face 30 of the lower roller 1 and is preferably at mostequal to the radius of the edge disks 4, 5. The axis of curvature is inthe vicinity of the axis of the lower roller 1. Its exact locationintrinsically depends on the position at the time of the base body 32and the flap 33. Preferably the narrow boundary face 35 is also curvedin a corresponding way.

A disk 47 is seated between the edge disk 5 and the side wall 8,adjacent to it, of the fixed frame 6 and is solidly joined to the sidewall 8. At least in the region adjacent to the end wall 9, it protrudespast the circumference of the edge disk 5. In this region, an inneradapter 48 is secured to the disk 47. This adapter also engages theannular channel, which is defined by the jacket face 30 of the lowerroller 1 and by the inside faces of the two edge disks 4, 5. The inneradapter 48 is embodied in one piece. It has a base 51, which is providedwith oblong slots 49, 50, and an adjoining flange 52 of crescent-shapedcross section, which protrudes in the direction toward the roller gap 3deeply into the hollow space located between the flap 33 and the jacketface of the lower roller 1. Tangs 53, 54 which are joined to the disk 47protrude into the oblong slots 49, 50, so that--similarly to what hasbeen described above for the base body 32--a displacement and locking inthe region of a circular arc is possible, in this case naturally aroundthe axis of the lower roller 1.

The inner adapter 48 has a curved inner wall face 55, which conformsclosely to the jacket face 30 of the lower roller 1. A likewisecylindrically curved outer wall face 56 faces toward the flap 33. Itsradius of curvature is greater than the radius of the jacket face 30 butless than the radius of the edge disks 4, 5. The axis of curvature islocated in the vicinity of the axis of the lower wall 1. The inner wallface 55 and the outer wall face 56 form an edge 57 with a very acuteangle, which--similarly to a stripper knife--rests on the jacket face 30of the lower roller 1. It is located approximately perpendicular,or--depending on the point at which the base 51 is locked--laterallyoffset from the perpendicular below the edge 36 of the base body 32.

In the vicinity of the edge 57, the inner adapter 48 has recesses 58 onthe side toward the lower roller 1. These recesses can be connected viabores 59 to lines for delivering pressurized medium. Between the lowerwall face of the outer adapter 29, which face comprises the boundaryface 35 and the curved wall face 46, on the one hand and the outer wallface 56 on the other, there is a curved compression chamber 60 ofrectangular cross section, which in the position of the flap 33 shown inFIG. 3 becomes narrower toward its orifice 61. The orifice 61 is spacedapart from and below the plane 62 of the roller gap 3. The length of thecompression chamber 60, that is, the distance from the roller gap 3 tothe orifice 61, is markedly larger in FIG. 3 than the difference betweenthe outer radius of the edge disk 4, 5 and the radius of the jacket face(30). Over the entire length, the compression chamber 60 is laterallybounded by the inside faces of the edge disks 4, 5.

The exemplary embodiment shown in FIG. 4 differs from the exemplaryembodiment described above in particular in the different shape anddisposition of the outer adapter 63. It is embodied in one piece and hasa cylindrically curved ball face 64 facing toward the lower roller 1. Itis rigidly secured to a lever 65 which is pivotable about the axis ofthe upper roller 2. By means of a contact pressure device, of which FIG.4 only in suggested fashion shows a hydraulically or pneumaticallyactuated piston rod 66, the outer adapter 63 can be loaded with a forceaimed at the lower roller 1.

In this exemplary embodiment again, the inside faces of the edge disks4, 5, over the entire length of the roller gap 3 up to the orifice 61,form two opposed boundary faces of the compression chamber 60. A thirdboundary face is formed by the curved wall face 64. The outer wall face56 of the inner adapter 48--analogously to the exemplary embodimentdescribed above--forms the fourth boundary face.

The exemplary embodiment of FIG. 5 differs from the first exemplaryembodiment described above in particular in that there is no inneradapter. The fourth wall face of the compression chamber 60, oppositethe outer adapter 29, is formed here by the zone of the jacket face 30located in this angular region at any given time.

A stripper 67 is seated in front of the orifice 61 of the compressionchamber 60; it is displaceable and lockable--similarly to what has beendescribed in conjunction with the inner adapter 48. It has a curvedboundary face 68, which conforms to the jacket face 30 of the lowerroller 1, and a flat slide face 69 for diverting the crimped materialemerging from the orifice 61. The two faces 68, 69 form a stripper edge70. The slide face 69 forms an angle of 30 to 40° with an imaginarytangential face that touches the jacket face 30 at the stripper edge 70.The size of the angle is uncritical over a side range. However, itshould not be any greater than approximately 80°.

The device is suitable in particular for processing yarn cables in therange between 10,000 and 100,000 dtex.

What is claimed is:
 1. A device for crimping synthetic thread bundles orstrips, comprising a machine frame; two rollers supported in a machineframe and forming between their jacket a narrow roller gap fordelivering a thread bundle or strip, said rollers including a firstroller and a second roller arranged so that said first roller isprovided on its face ends with edge disks which embrace said secondroller with slight play and form therebetween an annular channel, saidedge disks having inside faces which over an entire length of saidcompression chamber from said roller gap to said orifice form twoopposed boundary faces; a compression chamber to which the thread bundleor strip is delivered and which has an orifice, said compression chamberhaving a rectangular cross-section and being enclosed by first, second,third, and fourth boundary faces, said compression chamber being locatedin said annular channel between said edge disks; an outer adaptercontacting said second roller in scrapper like fashion, said outeradaptor engaging said annular channel and having a wall face orientedtoward said first roller and forming said third boundary face of saidcompression chamber; and drive mechanisms provided for said two rollersand having motors which are designed for a circumferential speed of saidrollers of up to at least 1,000 m/min.
 2. A device as defined in claim1, wherein said orifice is spaced apart from a plane of said roller gapon a side on which said first roller is located.
 3. A device as definedin claim 1, wherein said third boundary face and said fourth boundaryface opposite it are curved cylindrically over at least a part of theirlength so that axes of curvature of said third and fourth boundary facesare located at a same side of a plane of said roller gap as said firstroller.
 4. A device as defined in claim 1, wherein said outer adaptorhas a base body adjacent to said second roller and a flap pivotablyconnected to said base body and extending as far as said orifice; andfurther comprising a contact pressure device which loads said flap witha force acting in a direction of said first roller.
 5. A device asdefined in claim 4, wherein said base body is displaceable over acircular arc about an axis of said second roller and is lockable invarious angular positions.
 6. A device as defined in claim 2, whereinsaid outer adaptor is formed of one piece and is pivotable about an axisof said second roller; and further comprising a contact pressure devicewhich loads said outer adaptor by a force acting in a direction of saidfirst roller.
 7. A device as defined in claim 1, and further comprisingan inner adaptor which contacts said first roller in scrapper likefashion and is seated between the jacket face of said first roller andsaid third boundary face, said inner adaptor having a wall face which isremote from said first roller and forms said fourth boundary face.
 8. Adevice as defined in claim 7, wherein said inner adapter is displaceableover a circular arc about an axis of said first roller and is lockablein various angular positions.
 9. A device as defined in claim 1, whereina jacket face of said first roller forms said fourth boundary face; andfurther comprising a stripper secured to said machine frame upstream ofsaid orifice and engaging said annular channel.
 10. A device as definedin claim 1, wherein said outer adaptor has recesses for delivering amedium into a gap between its edge and a jacket face of said secondroller.
 11. A device as defined in claim 7, wherein said inner adaptorhas recesses for delivering a medium into a gap between its edge and thejacket face of the second roller.
 12. A device as defined in claim 9,wherein said stripper has recesses for delivering a medium into a gapbetween a stripper edge and a jacket face of the second roller.